Fuel feeding apparatus

ABSTRACT

A device for intimately intermixing a liquid fuel, air, and preferably also a metered proportion of water, for delivery to an internal combustion engine or other fuel burning mechanism, the device including a rotor to which the fuel and water are delivered for centrifugal discharge radially outwardly in finely divided mist form, with the rotor preferably carrying a large number of minute fibers projecting radially outwardly and along which the liquids flow in a manner subdividing the liquids into minute droplets. The rate of delivery of the fuel and water is regulated in accordance with the rate of flow of air through the device, and by a control structure actuable by the air.

United States Patent Related US. Application Data [63] Continuation-impart of Ser. No. 772,551, Nov.

1, 1968, abandoned.

[52] US. Cl. 261/18 A, 261/50 A, 261/84, 261/88, 261/67, 123/25 1.. [51] Int. Cl ..F02m 9/12 [58] Field of Search ..261/50 A, 18 A, 83, 85, 88, 261/84, 67; 123/25 L [56] References Cited UNITED STATES PATENTS 3,512,508 5/1970 Winkler ..261/50 A 2,583,406 l/1952 Arnold ..261/50 A 2,229,313 l/194l Snyder ..26l/50 A 3,265,374 8/1966 Morton ..261/50 A 2,887,309 5/1959 Raynor ..261/50 A 1,547,323 7/1925 Hennequin ..261/50 A Carter 1451 Qct. 31, 1972 [54] FUEL FEEDING APPARATUS 2,636,488 4/1953 Cedarholm ..261/18 A 7 I t z I 1,362,389 12/1920 Brandon ..261/18 A 2] g'gggg ggf; 3 g 3,105,745 10/1963 V1611 ..23/252 3,199,847 8/1965 Wahnish ..261/85 x [22] Filed: July 21, 1970 1,349,835 8/1920 Jennings ..261/50 A 3,544,084 12/1970 Macrow ..26l/83 [21] APP! 3,538,657 11/1970 Macrow ..55/231 Primary Examiner-Tim R. Miles Attorney--William P. Green [57] ABSTRACT A device for intimately intermixing a liquid fuel, air, and preferably also a metered proportion of water, for delivery to an internal combustion engine or other fuel burning mechanism, the device including a rotor to which the fuel and water are delivered for centrifugal discharge radially outwardly in finely divided mist form, with the rotor preferably carrying a large number of minute fibers projecting radially outwardly and along which the liquids flow in a manner subdividing the liquids into minute droplets. The rate of delivery of the fuel and water is regulated in accordance with the rate of flow of air through the device, and by a control structure actuable by the air.

2 Claims, 13 Drawing Figures PATENTEDumm m2 SHEET 1 OF 4 -qal W B 9. 1 r ED v i m g UH! 2 i T i gill. 5 w x l a @L w P a a FUEL FEEDING APPARATUS CROSS REFERENCE TO RELATED APPLICATION This application is a continuation-in-part of my copending application Ser. No. 772,551 filed Nov. 1, 1968 on Fuel Feed Device, now abandoned.

BACKGROUND OF THE INVENTION This invention relates to devices for intermixing liquid fuel and air to produce a bumable mixture, preferably containing a metered quantity of moisture in conjunction with the air and fuel to improve the burning results. While it is to be understood that equipment of the present type can be utilized for supplying a bumable mixture for any of numerous different types of apparatus, e.g., burners and the like, the invention will be described primarily as applied to, and is in certain particular respects especially designed for, the preparation of a bumable mixture in a carburetor type of structure for an internal combustion engine or other fuel burning engine.

Though numerous different types of carburetors and other units for preparing a combustible mixture have been devised in the past, none of these prior arrangements with which I am familiar has proven totally acceptable in actual practice. The carburetors currently in use on motor vehicles do not intermix the fuel and air as thoroughly as would be desired, with the result that much of the fuel accumulates on the walls of the intake manifold and other intake passages, and the mixture ultimately reaching the cylinders is not of accurately predeterminable proportions. Further, the proportion of fuel introduced into the air stream varies under different operating conditions, such as acceleration, deceleration, etc., with resultant waste of much of the fuel, inefficiency in operation, and emission of large amounts of unburned hydrocarbons and similar contaminants into the atmosphere. Attempts to overcome the operational disadvantages of conventional carburetors have resulted in the development of numerous extremely complex and expensive types of carburetor accessories, which themselves have been less than optimum in functioning, and have been so expensive as to virtually preclude their use on any standard vehicle.

SUMMARY OF THE INVENTION A fuel feed device constructed in accordance with the present invention is capable, with an extremely simple structure, of producing a bumable mixture whose proportions are very accurately predeterminable and controllable, and whose proportions do not vary under different operating conditions. Further, in a device of the-present type, the intermixture of the fuel and air, and preferably also a proportional quantity of water, is so intimate as to assure maintenance of that intermixture, without separation of the fuel and water from the air, while the mixture is passing through the inlet passages and into the cylinders, so that fuel and/or water do not separate out on those inlet passages, and so that the mixture is in its most readily combustible form at the time of actual burning.

The intimate mixture of the fuel and air is attained by use of a rotor structure which is driven at a relatively high rate of speed, so that fuel fed to the interior of the rotor is delivered radially outwardly in centrifugal manner, and is discharged centrifugally from the rotor in the form of a finely divided mist, which is then mixed with a stream of air flowing to the engine. The rotor preferably carries a large number of fine fibers, which project radially outwardly with respect to the axis of the rotor, and along which the fuel flows as it moves radially outwardly under centrifugal action. The fuel discharges from the rotor in the form of extremely minute droplets, which are small enough and light enough to be effectively suspended in the air stream, and be carried axially with the air without contacting a surrounding wall of the device, and which do not appreciably agglomerate during flow of the air to the engine cylinders. In a preferred arrangement, the rotor may include a porous sheet of material, desirably woven fabric, extending annularly about the axis of the rotor and presenting a nap projecting radially outwardly and defining the mentioned fibers.

The delivery of fuel and water to the rotor is controlled by an element positioned in the path of air flow through the device and adapted to be actuated to different positions varying in accordance with the rate of such air flow. Thus, the fuel and water delivery are controlled automatically, to always produce a mixture with the air of optimum proportions. The fuel and water regulation valve structure may be a pinch valve unit, actuated by an air flow responsive flapper device.

Certain particular features of the invention relate to a preferred critical relationship between the size of the air actuated element and the area of the air flow path at the main throttle valve of the device, which relationship is highly important for assuring against hunting and fluttering of the air actuated element and controlled fuel valve in use. More particularly, the air deflected element should have an area exposed to the force of the flowing air which is at least about ten times as great as the minimum effective cross-sectional area of the air flow path at the main throttle valve when the latter is fully open.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other features and objects of the invention will be better understood from the following detailed description of the typical embodiments illustrated in the accompanying drawings, in which:

FIG. 1 is a fragmentary essentially diagrammatic representation of a carburetor device constructed in accordance with the invention, and shown positioned on an engine;

FIG. 2 is an enlarged view of the carburetor taken partially on line 2-2 of FIG. 1, and partially on lower planes to illustrate the interior portions of the carburetor;

FIG. 3 is a further enlarged vertical section taken primarily on line 3-3 of FIG. 2;

FIG. 4 is a fragmentary view taken on line 4-4 of FIG. 3;

FIG. 5 is a fragmentary vertical section taken in the plane of FIG. 3, but showing the fuel and water regulating flapper element in an open position;

FIG. 6 is an enlarged fragmentary essentially vertical section taken on line 6--6 of FIG. 5;

FIG. 7 is a vertical section taken on line 7 7 of FIG.

FIG. 8 is a view similar to FIG. 7, but showing the liquid supply pinch valve in closed condition;

FIG. 9 is a vertical axial section through the rotor of FIG. 1, with a portion of the rotor being shown in elevation;

FIG. 10 is a reduced scale view taken on line 10-10 of FIG. 9;

'FIG. 1 1 is a greatly enlarged somewhat diagrammatic representation of the velvet-type fiber carrying material of the device, taken on line 1111 of FIG. 10;

FIG. 12 is a further enlarged representation of the fibers, and the manner in which droplets form at their outer extremities; and

FIG. 13 is a vertical section through a variational type of rotor.

DESCRIPTION OF THE PREFERRED EMBODIMENTS With reference first to FIG. 1, I have illustrated diagrammatically at 10 an internal combustion engine whose intake manifold is illustrated at 11, and which utilizes a carburetor l2 constructed in accordance with the invention. An essentially conventional circular air cleaner 13 may be positioned on the carburetor, for cleaning the air flowing to the engine, but will not be described indetail. The butterfly type throttle valve 14 of the carburetor is actuated by the usual accelerator pedal 15, through a conventional linkage represented diagrammatically at 16.

As seen bestin FIG. 3, the carburetor 12 includes a hollow body 17, which is desirably annular about a vertical axis 18, and which may be formed sectionally of a first lower and main bowl section 118, a cover 19, and an upwardly projecting tubular section to the upper edge of which is mounted the air cleaner 13. Lower section 17 of the. carburetor body may taper downwardly from an upper relatively large diameter cylindrical portion 22 to a reduced diameter essentially cylindrical portion 23 within which the butterfly valve 14 is mounted to pivot about a shaft or axis 24 from the broken line closed position of FIG. 2 to an open position such as that shown in full lines. A lower flange 25 of section 17 of the carburetor body may be suitably secured by bolts 26 to the intake manifold 11, to deliver an air-fuel-water mixture into that intake manifold.

Section 19 of the carburetor body may have a vertically extending cylindrical portion 26 resting on and forming a continuation of portion 22 of section 17, and terminating upwardly in an annular inturned flange 27 to which upwardly projecting tubular section 20 is secured by screws 28 or the like. Sections 17 and 19 are suitably secured together in annularly sealed relation with respect to one another by appropriate screws or other fasteners 29..In flowing toward the engine, air enters the upper end of upper tubular section 20 of the carburetor body, and flows downwardly within that body for discharge past butterfly valve 14 of the engine.

Fuel and water are fed into the air stream by a rapidly turningrotor 30 driven continuously and at a uniform rate of speed by a motor 31. This is typically and desirably an electric motor, driven by the battery 32 of the vehicle (FIG. 1), under the control of the usual ignition key switch 33, which, besides serving its conventional function of energizing the ignition circuits, also closes the circuit to motor 31 and commences rotation of the motor when the ignition is turned to its on position.

The driven shaft 34 of motor 31 (FIG. 3) projects downwardly along the previously mentioned central vertical axis of the carburetor body, and turns about that axis with the rotor. The housing of the motor is mounted stationarily within the carburetor body (desirably projecting upwardly therefrom as shown), with the mounting preferably being effected by attachment of the motor housing to the upper side of an annular horizontal rigid, typically metal, plate 35, whose annular peripheral edge 36 is retained and clamped tightly between opposed shoulders on the two body sections 17 and 19, in a manner forming an annular fluid tight seal between plate and the carburetor body. Plate 35 contains a central opening 37 through which shaft 34 projects downwardly. The plate also contains a large number of circularly spaced identical circular apertures 38 (FIG. 2) near the periphery of the disk, and through which air flows downwardly past the downwardly deflectible flapper element.

Element 39 may be considered as a flat annular part formed of sheet metal or the like, and having a peripheral edge 40 of a diameter slightly less than the internal diameter of portion 22 of body section 17. Internally, element 39 has a circular edge 41 of a diameter considerably less than the minimum diameter (about axis 18) of air passing apertures 38 in plate 35, so that in its FIG. 3 closed position, element 39 closes the apertures 38 and prevents flow of air downwardly therethrough. When swung downwardly to an open position such as that shown in FIG. 5, element 39 opens the apertures 38 to the downflow of air through these apertures and radially inwardly as indicated by the arrow 42 of FIG. 5, to then flow downwardly past inner edge 41 of element 39 and toward butterfly valve 14. Element 39 is spring urged upwardly, and swings downwardly against the tendency of its return springs to different positions varying in accordance with the rate of air flow through the apparatus as controlled by the butterfly valve 14.

At its right edge as seen in FIGS. 2, 3 and 5, element 39 may carry a screw or pin 34', which is threadedly and rigidly connected into an opening in element 39, and projects upwardly through one of the apertures 38 in plate 35. An upwardly tapering spiral coil spring 44 is disposed about screw 34, and bears upwardly against a head 45 of the screw and downwardly against plate 35 to yieldingly resist downward swinging movement of element 39. At the diametrically opposite side of element 39 (left side of the figures), element 39 adjustably carries a second screw 46, which may typically be threaded into a nut 47 rigidly welded or otherwise secured to element 39, with this screw 46 being accessible for adjustment through one of the apertures 38 in plate 35, and through a registering aperture 48 formed in the top wall of the carburetor body (FIG. 3), to enable adjustment of the proportion of liquid delivered into the air by rotor 30 at idle.

Liquid fuel, e.g., gasoline, kerosene, diesel, fuel, or any other readily combustible liquid fuel, is delivered to the device through a line 49 (FIGS. 1 and 3), from the usual fuel tank 50 and fuelpump 51. Similarly, water for mixture with the fuel is fed to the device through a line 52, leading from a pump 53 which draws water from an appropriate water tank 54. The two pumps 51 and 53 may be substantially the same as conventional fuel pumps, being driven by the cam shaft of the engine itself when the latter is in operation, to thus continuously supply fuel and water under pressure to the carburetor.

Lines 49 and 52 may enter the device through appropriate openings in cover section 19 of the carburetor body, and may then pass downwardly through apertures 55 in plate 35 (FIG. 3) for connection to a deformable pinch valve element 56, whose discharge end leads into a pair of tubes 57, which are mounted stationarily by a part 68 secured to plate 35, and which lead downwardly into the interior of rotor 30. Pinch valve 56 has the configuration illustrated in FIGS. 6, 7 and 8, including a single unitary elastomeric element 58 formed of rubber or the like (desirably neoprene). This element 58 contains two identical parallel elongated passages 59 and 60 (FIG. 6) through which the fuel and water respectively flow into the two depending discharge lines 57.

Pinch valve element 56 is constrictable from its open position of FIG. 7 to its closed position of FIG. 8 by swinging movement of an actuating lever 61 from its FIG. 5 position to its FIG. 2 position. This lever is mounted for its swinging movement by two bearing lugs 62 on the lever, containing aligned apertures through which a horizontal mounting shaft 63 extends, with the shaft also extending through registering aligned openings in a pair of support lugs 64 rigidly attached to and projecting downwardly from the underside of plate 35. The left end portion 65 of lever 61 engages the previously mentioned adjustable screw 46 carried by element 39, to swing the lever downwardly in accordance with the downward movement of element 39. Lever 61 is suitably spring returned upwardly, as by an elongated generally U-shaped spring 66 (FIGS. 3, 4 and 5), having two ends 67 bearing upwardly against the underside of plate 35. From their ends 67, the two arms of spring 66 extend at 70 to the location of a pair of coils 71 disposed about and acting downwardly against shaft 63, and then converge at 72 to the location of a cross piece 73 which bears upwardly against lever 61.

As seen best in FIGS. 6, 7 and 8, lever 61 has at its right extremity an upturned flange 74, having an upper horizontal edge 75 which is adapted to engage and deform pinch valve 56 in response to swinging movement of the lever. At its upper side the top horizontal surface 76 of the pinch valve may bear upwardly against a horizontal undersurface 77 of a rigid backing part 78, suitably secured to the underside of plate 35. The pinch valve and its actuating parts are desirably so constructed as to regulate the flow of water and fuel in exact proportion to one another. Screw 46 is so adjusted as to cause lever 61 to substantially close both of the fluid passages 59 and 60 when element 39 is in its upper FIG. 3 position, and to commence opening of those passages when element 39 is deflected downwardly to any extent beneath its FIG. 3 position, with the rate of liquid flow through passages 59 and 60 being proportional to the rate of air flow downwardly past element 39.

Rotor 30 is so constructed as to have a large number of small diameter fibers projecting radially, outwardly from its periphery, to effect maximum subdivision of the water and fuel into minute droplet form as these liquids are discharged radially outwardly from the rotor. A preferred structure for the rotor is illustrated in FIG. 9, in which the rotor is shown as having a rigid body formed of two typically metal annular sections 79 and 80 centered about axis 18, and secured together by evenly circularly spaced screws 81. Body 79-80 and the remainder of the rotor'are of course balanced about axis 18, to rotate rapidly without vibration. The body is secured rigidly to the lower end of motor shaft 34, as by clamping section 79 against an annular shoulder 84 on the motor shaft, by means of a nut 83 connected onto the threaded lower end 84' of the shaft. To assure rotation of the rotor with the shaft, these parts may be appropriately keyed together.

At its upper side, the rotor body 79-80 forms a circular upwardly opening liquid receiving compartment or chamber 85, into which the metered fuel and water are fed through feed lines 57 from the pinch valve 56. This annular chamber preferably has a horizontal bottom wall 86, and a frustoconical annular side wall 87 which tapers upwardly to a reduced diameter upper inlet opening 90. The two liquids flow generally radially outwardly from the bottom of chamber through appropriate circularly spaced passages 93 formed in the body of the rotor and to an outer annular groove or compartment 91. The passages thus introduce the liquids into this compartment 91 at a series of evenly circularly spaced locations.

Extending about the periphery of rotor body 79-80, there is provided an annular piece of woven fabric 94, of a vertical extent corresponding to that of the peripheral portion of the rigid body, and with the upper and lower edge portions of the fabric 94 being clamped to the body by annular clamping rings 95 and 96. Thus, the fabric 94 bridges across compartment 91, so that any liquid leaving the rotor must pass through the porous fabric. The fabric is chosen to present a multitude of radially outwardly projecting fibers 97 (FIGS. 11 and 12), of very small diameter, which are distributed in very closely spaced relation across the entire surface of the fabric. For best results, the individual fibers do not contact one another at their outer extremities 98. The fibers are of a substance which is impervious to the fuel and water, and is desirably non-inflammable and is otherwise capable of withstanding high temperature backfire conditions without damage, and which additionally has sufficient strength to maintain its integrity and resist wear and deterioration under long periods of use. The currently preferred material for the fibers, and for the fabric which carries the fibers, is glass, though various other materials may be used, such as tetrafluoroethylene polymer, the silicones, the acrylics, nylon, and other resinous plastic substances. The diameters or maximum transverse dimensions of the individual fibers should preferably be not greater than about 10 denier, and for best results not over about 5 denier, optimally between about onehalf denier and 2 denier. The effective length I of the fibers (see FIG. 11), i.e., their free length outwardly beyond the backing fabric or other carrying structure, may vary for different particular uses, preferably being between about one thirty-second and three-fourths of an inch.

To attain the desired arrangement of radially outwardly projecting fibers, I find a fabric having a velvet type weave to be very satisfactory. More particularly,

this velvet material has a woven backing as illustrated at 99 in the greatly enlarged somewhat diagrammatic representation of FIG. 11, with U-shaped bundles of the fibers 97 being doubled about and retained by the fibers of the fabric backing, so that their outwardly projecting ends serve the purpose of the liquid distributing fibers.

To now describe the manner of operation of the device illustrated in FIGS. 1 through 12, assume that the ignition key has been turned and that motor 31 is therefore driving rotor 30 rapidly and continuously at a uniform rate of speed (desirably at least about 3,000 rpm, and for best results between about 4,000 rpm and 4,500 rpm). Also assume that throttle valve 14 is initially closed, and that element 39 is in its FIG. 3 closed position. If the internal combustion engine 10 is then started, with partial opening of the throttle valve 14,

the vacuum of the engine commences to draw air downwardly through the interior of the carburetor body, and element 39 is therefore actuated downwardly by the air to a partially open position similar to that shown in FIG. 5. The extent of opening of element 39 depends upon the rate of flow of the air downwardly through the carburetor. This downward deflection of element 39 acts through lever 61 to partially open the previously closed liquid passages 59 and 60 in pinch valve element 56, to allow water and fuel to flow into rotor 30 at a rate proportional to the rate of flow of the air downwardly through the carburetor. This water and fuel are thrown radially outwardly within the rotor body through passages 93, and then through the porous fabric 94. These liquids then flow outwardly, still under centrifugal action, along the surfaces of the very small dimension fibers 97, as indicated at 100 in FIG. 12, to ultimately form minute droplets 101 of water and fuel discharging into the air at the periphery of the rotor and in the form of a finely divided mist. These droplets are of such extremely finely divided form (usually under 1 micron in maximum dimension) as to have insufficient mass to continue their radially outward movement to the location of the outer peripheral wall of the carburetor body. Instead, these minute droplets are immediately withdrawn downwardly by the stream of air, for passage past the butterfly valve 14 and through the intake manifold of the engine to the cylinders. The finely divided particles remain in suspended form along this entire course of travel, and into the engine, and do not coalesce on the surfaces of the carburetor walls or intake passages, to thus result in optimum combustion in the cylinders. Also, when the fuel burns in the cylinders, the moisture present in the mixture converts to steam, which by its expansion adds to the power applicable to the pistons. Additionally, the absorption of some of the generated heat by the moisture prevents the development of excessive temperatures in the cylinders.

FIG. 13 shows a variational type of rotor which may be employed in the system, and which includes a twosection rigid rotor body 79a, 80a, secured to and driven by a motor shaft 34a and forming an annular peripheral groove 910 within which an annular series of elongated fibers 97a are received in doubled essentially Ushaped positions. The fibers are retained in their illustrated positions by an annular clamping wire or ring 105, with the individual fibers extending radially outwardly and terminating at radially outer extremities 98a. Fuel and water are fed into a compartment a in the rotor body, to flow outwardly therefrom through passages 93a, into the groove 91a, for contact with the fibers 97a, so that the liquids may flow radially outwardly along these fibers for ultimate discharge in finely divided droplet form from the tip ends 98a of the fibers.

While it is preferred in each of the forms of the invention that the individual fibers be slightly spaced from one another, it is found in actual practice that satisfactory results can be attained even though adjacent fibers are in most instances in direct contact.

With reference again to FIGS. 2, 3 and 5, it is noted that the upper surface of the air deflectible element 39, which surface is exposed to and actuable by the downward force of air entering the carburetor housing through apertures 38, desirably has an effective area (in a horizontal plane, i.e., transversely of the direction of air flow thereagainst), which is relatively large as compared with the effective horizontal cross-sectional area of the air flow passage within lower throat 23 of the carburetor body at the location of throttle valve 14. In the particular arrangement illustrated in FIG. 3, the horizontal area of element 39 is more than 10 times the minimum effective transverse cross-sectional area of the air passage at the throttle valve when the throttle valve is fully opened. To attain an effective fuel controlling operation, this ratio should preferably be at least about 10:]. If the element 39 is not thus made relatively large in effective area as compared with the most restricted portion of the air passage at the throttle valve, there is a decided tendency for element 39 to hunt or flutter in a manner introducing unwanted variations into the rates of air, fuel and water flow, and thus detracting from the operational characteristics of the device.

I claim:

1. A fuel feed device comprising a hollow housing through which air flows in passing to a fuel burning unit; a throttle valve for regulating the rate of flow of air through said housing; a rotor in the housing along the path of air flow therethrough and operable to feed fuel into the air for admixture with the air; a motor for driving said rotor rapidly about an axis and energized by power other than the power of air flowing through the housing; an element, in addition to said rotor and the other previously recited elements, positioned in the path of said air flow and deflectible by the flowing air to positionsvarying in accordance with the rate of air flow through the housing; means for delivering liquid fuel to said rotor at a location to be fed thereby into said flow of air, said last mentioned means including valve means actuable by said element to regulate the rate of fuel delivery to the rotor in accordance with said deflection of said element; a plate mounting said motor and rotor and disposed generally horizontally across the path of said air, said plate containing a series of circularly spaced apertures generally about the location of said motor and rotor; said element being essentially annular and disposed at the underside of said plate in a position closing said apertures and mounted to swing downwardly about essentially one side edge of the element to open the apertures; spring means yieldingly urging said element upwardly to closed position; said valve means including a flexible pinch valve body con- 9 sweet LII said mechanism includes a lever mounted pivotally to the underside of said plate and having a first end deflectible downwardly by said element and a second end adapted to engage and defonn said pinch valve body. 

1. A fuel feed device comprising a hollow housing through which air flows in passing to a fuel burning unit; a throttle valve for regulating the rate of flow of air through said housing; a rotor in the housing along the path of air flow therethrough and operable to feed fuel into the air for admixture with the air; a motor for driving said rotor rapidly about an axis and energized by power other than the power of air flowing through the housing; an element, in addition to said rotor and the other previously recited elements, positioned in the path of said air flow and deflectible by the flowing air to positions varying in accordance with the rate of air flow through the housing; means for delivering liquid fuel to said rotor at a location to be fed thereby into said flow of air, said last mentioned means including valve means actuable by said element to regulate the rate of fuel delivery to the rotor in accordance with said deflection of said element; a plate mounting said motor and rotor and disposed generally horIzontally across the path of said air, said plate containing a series of circularly spaced apertures generally about the location of said motor and rotor; said element being essentially annular and disposed at the underside of said plate in a position closing said apertures and mounted to swing downwardly about essentially one side edge of the element to open the apertures; spring means yieldingly urging said element upwardly to closed position; said valve means including a flexible pinch valve body containing a passage for said fuel and a second passage for delivering water to said rotor for admixture with the fuel and air; and mechanism actuable by said element to close said passages in the pinch valve body in response to upward swinging movement of said element.
 2. A fuel feed device as recited in claim 1, in which said mechanism includes a lever mounted pivotally to the underside of said plate and having a first end deflectible downwardly by said element and a second end adapted to engage and deform said pinch valve body. 